The next episode of Doctor Who has been toned down after producers decided one scene was "a bit too horrible".

The episode, to be shown on BBC One on Saturday, sees the Doctor travel back to tackle a strange virus in the Blitz.

It turns former One Foot in the Grave actor Richard Wilson's face into a gas mask - but producers have cut out the sound of his skull cracking.

But producer Phil Collinson said it was still the scariest episode so far. "It was about time we did a scary one."

"It's a little thing involving the scene with Richard Wilson's character and the gas mask," said producer Phil Collinson.

Doctor Who is well-known for being spooky and scary

Phil Collinson, producer

"The whole sound effect that went with that was a lot more visceral. We watched it for the first time and said that was crossing over the line because it was a bit too horrible."

But he said the episode, titled The Empty Child, was still the scariest yet.

"It was about time we did a scary one," Mr Collinson said. "Doctor Who is well-known for being spooky and scary."

The story is set during World War II

The series has also caused controversy over another character, Captain Harkness, who flirts first with Rose Tyler (Billie Piper) - before turning his attention to the Doctor, played by Christopher Eccleston.

News of the episode comes days after the BBC announced the DVD of the new series - the first since 1989 - would not be available to children under 12 because of a scene where a Dalek is tortured.